In activities involving document feeding, a need has existed for a feeding apparatus that is able to feed documents of different thicknesses and a feeding apparatus that acts as a buffer between adjacent conveyors. The latter need is occasioned by two conveyors placed in line with one another wherein the feeding conveyor operates at times faster than the receiving conveyor. In this situation some type of buffer mechanism is required between the fast and slow conveyor so that the documents may be stored and simultaneously supplied to the slower operating conveyor in the same sequence without any mishap. An example of the need of such a buffer mechanism is between a variable speed collator and an inserter.
Although many different combinations have been attempted for both a mixed thickness document feeder and an acceptable buffer, to the inventor's knowledge there is no single device that is capable of serving both functions satisfactorily.